Tính hợp lý a) -(3/10 - 6/11) - (21/30 - 5/11) b) (13/5 + 7/16) - (11/16 - 12/10)
Giải thích
a)
−310−611−2130−511=−310+611−710+511=−310−710+611+511=−1+1=0
b)
135+716−1116−1210=135+716−1116+65=135+65+716−1116=195+−14=7620+−520=7120
a)
−310−611−2130−511=−310+611−710+511=−310−710+611+511=−1+1=0
b)
135+716−1116−1210=135+716−1116+65=135+65+716−1116=195+−14=7620+−520=7120